Battle Pets by Zone

Pet Battle: [1-2] Dun Morogh; [1-2] Durotar; [3-4] Northern Barrens; [7-9] Northern Stranglethorn; [9-10] Southern Barrens; [16-17] Blasted Lands; [17-18] Hellfire Peninsula; [18-19] Nagrand (Outland); [25] Spires of Arak; [25] Nagrand (Draenor)

Pet Battle: [13-14] Searing Gorge; [15-16] Un'Goro Crater; [15-16] Burning Steppes; [16-17] Blasted Lands; [22-23] Mount Hyjal

Pet Battle: [1] Orgrimmar; [12-13] Eastern Plaguelands; [13-14] Thousand Needles; [15-16] Burning Steppes; [16-17] Blasted Lands; [16-17] Silithus; [17-18] Hellfire Peninsula; [18-20] Blade's Edge Mountains; [20-21] Shadowmoon Valley (Outland); [23-24] Twilight Highlands

Pet Battle: [16-17] Blasted Lands

Pet Battle: [1] Orgrimmar; [1] Gilneas; [1-2] Elwynn Forest; [1-2] Dun Morogh; [1-2] Tirisfal Glades; [1-2] Teldrassil; [1-2] Gilneas City; [3-6] Ghostlands; [3-6] Azshara; [5-7] Stonetalon Mountains; [6-7] Hillsbrad Foothills; [11-12] The Hinterlands; [12-13] Dustwallow Marsh; [12-13] Eastern Plaguelands; [14-15] Swamp of Sorrows; [16-17] Blasted Lands; [17-18] Winterspring; [20-22] Howling Fjord; [22-23] Zul'Drak; [22-23] The Storm Peaks; [23-25] Shadowmoon Valley (Draenor)